Tektronix Keithley 6517B, Руководство пользователя

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Section 3: Connections Model 6517B Electrometer User's Manual
3-12 6517B-900-01 Rev. B August 2022
Figure 22: Floating voltage source
Test fixtures
Whenever possible, use shielded low-leakage test fixtures to make precision measurements.
The Model 8009 test fixture allows volume resistivity in the range of 10
3
Ω -cm to 10
18
Ω -cm, and
surface resistivity in the range of 10
3
Ω to 10
17
Ω. Features include:
•
A 3-lug triaxial connector and dual binding posts to simplify connections to the 6517B.
•
Guarded electrodes that can accommodate samples up to 1/8" thick and 4" × 4"
.
•
Safety Interlock: When connected to the 6517B, the voltage-source goes into standby when the
test fixture lid is open.
•
Screw terminal on the test fixture chassis for connection to safety earth ground.
You can also build a custom test fixture. The following topics provide guidelines when building a
test fixture.
Interlock
When a normally-open SPST momentary switch is properly implemented as a safety interlock, the
voltage source goes into standby whenever the test fixture lid is open or ajar. The switch must be
mounted inside the test box and must close when the lid of the test fixture is closed. Opening the lid
must cause the interlock switch to open. There must never be enough clearance to allow finger
access inside the box while the switch is closed. The interlock must be designed so that it cannot be
defeated. The Keithley Instruments Model 8009 test fixture provides an interlock that meets
these requirements.